Use a StreamTokenizer object to parse a string separated by commas

 Use a StreamTokenizer object to parse a string entered from the keyboard containing a series of data items separated by commas and output each of the items on a separate line.

 If you don't make '\n' a whitespace character, a comma will be necessary at the end of the last token. End-of-line terminates the input so only a single line is processed.

Here is some sample input and output:

red , "red and yellow", red and yellow, 123, 123.456, 1.2E10
  red
"red and yellow"
red and yellow
123
123.456
1.2E10

As you see, this tokenizer setup processes anything as tokens.

import java.io.StreamTokenizer;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.IOException;

public class ParseString {
  public static void main(String[] args) {
    char separator = ',';
    StreamTokenizer tokenizer = new StreamTokenizer(new InputStreamReader(System.in));
    tokenizer.resetSyntax();

    // Characters other than comma and special characters are word characters
    tokenizer.wordChars('\u0000', (char)(separator - 1));                 // Everything is a word character
    tokenizer.wordChars((char)(separator + 1), '\u00ff');                 // except for the separator
    tokenizer.whitespaceChars('\n', '\n');                                // Make end-of-line whitespace(and therefore a word delimiter)
    tokenizer.whitespaceChars(separator, separator);                      // Delimiter separates words
    tokenizer.eolIsSignificant(true);                                     // End-of-line to be reported as TT_EOL

    int type = 0;                                                         // Stores the value returned by nextToken()
    String token = null;                                                  // Will store the tokens that we find
    try {
      while((type = tokenizer.nextToken()) != StreamTokenizer.TT_EOL) {   // As long as we don't have EOL
        if(type == StreamTokenizer.TT_WORD) {                             // Check for a word
          System.out.println("  "  + tokenizer.sval.trim());              // and output it
        } else {
          assert false;                                                   // We only expect words
        }
      }
    } catch(IOException e) {
      e.printStackTrace();
      System.exit(1);
    }
  }
}

Output of Above Java Program
java, programs,and,Examples
java
programs
and
Examples